Influence of n-3 Polyunsaturated Fatty Acid in the Proliferative Activity of Lymphocytes During Experimental Infection with Paracoccidioides brasiliensis

Resumo

It has been shown that diets containing polyunsaturated omega-3 fatty acids may modulate the immune system. Paracoccidioidomycosis (PCM) is a systemic mycosis of great importance in Latin America, caused by the thermo-dimorphic fungus Paracoccidioides brasiliensis. The aim of this study was to evaluate the influence of n-3 PUFAs in lymphoproliferative activity in murine experimental PCM. Spleen lymphocytes from animals infected with an isolate of P. brasiliensis (Pb18) and fed with diets supplemented with flaxseed oil or a commercial diet for eight weeks, were obtained and cultured for evaluation of lymphoproliferative activity by MTT assay. In uninfected animals and those fed an enriched-flaxseed diet the evaluated lymphoproliferative activity was inhibited in the first week; however, this activity resumed at later stages. On the other hand, in animals infected and fed an enriched-flaxseed diet, the interaction between the stimulus given by the presence of the fungus and the action of n-3 PUFAs appeared to stimulate lymphocyte proliferation after the first week of infection. n-3 PUFAs are shown to influence lymphoproliferative activity of mice in experimental PCM.